isl.ac.cn.		30 IN SOA ns.isl.ac.cn. mail.isl.ac.cn. (
				20         ; serial
				28800      ; refresh (8 hours)
				3600       ; retry (1 hour)
				604800     ; expire (1 week)
				1800       ; minimum (30 minutes)
				)

isl.ac.cn.		30 IN TXT "v=spf1 include:spf.mail.cstnet.cn -all"

Mail exchangers:
isl.ac.cn.		30 IN MX 5 mx.cstnet.cn.

Name servers:
isl.ac.cn.		30 IN NS ns3.cstnet.cn.
isl.ac.cn.		30 IN NS ns4.cstnet.cn.